# Author:Sooele
import threading, time
def run(n):
semaphore.acquire() #信号量获取一把锁
time.sleep(1)
print("run the thread: %s\n" % n)
semaphore.release()
if __name__ == '__main__':
num = 0
semaphore = threading.BoundedSemaphore(5) # 最多允许5个线程同时运行
for i in range(20):
t = threading.Thread(target=run, args=(i,))
t.start()
while threading.active_count() != 1:
pass # print threading.active_count()
else:
print('----all threads done---')
print(num)
